Waterproofing



Patented Feb. 12, 1929.

UNITED STATES ATT oFFic.

STANLEY L. WILLIS AND WATSON H. WOODFORD, 0F BRIDGEPORT, CONNECTICUT, AS- SIGNORS TO- REMINGTON ARMS COMPANY, INC., A CORPORATION OF DELAWARE.

WATERPROOFING.

No Drawing.

This invention relates to the manufacture of waterproof loaded shot shells or cartridges and particularly to the waterproofing of the'top wad and the provision of a waterproof joint between the top wad and the shell b0 y.

In the manufacture of shot shells or cartridges, paper tubes for the shot shell bodies are rolled on a mandrel from a sheet of paper and secured by a suitable adhesive. The tube thus formed is waterproofed by the application thereto of a suitable waterproofing composition such for example, as the waterproofing composition disclosed 1n our copending application Ser. No. 29,797, filed May 12, 1925. To one end of the tube thus formed, a metallic head comprising a primer and a base wad is attached and a charge of powder, wadding and shot is then introduced through the open end of the tube. Upon the shot a closing or top wad is placed and the extending end of the shell tube is turned inward and downward or fcrimped against the top wad to securely hold the charge and the top wad in place.

It is of the greatest importance that not only the top wad, but also the periphery and the inturned end of the shell tube, and the joint between the tube and the top Wad be resistant to moisture; since the absorption of moisture by the wad or the tube causes these parts to swell and to become soft and flabby, while moisture within the shell deteriorates the powder. It is therefore necessary that the top wad, the crimp and the joint be carefully waterproofed.

The present invention comprises the discovery that a polymerizable oil or a composition including a polymerizable oil as an essential ingredient is a singularly effective agent for'watei'proofing the top wad and crimp. The waterproofing material may be applied after the 'top wad is in place, and either before or after the crimping operation. While a number of compositions comprising a polymerizable oil as their essential ingredlent have been found to be satisfactory for this purpose, a preferred composition consists of a mixture of a polymerizable oil and one of the class of substances known as driers, the prime function of the drier being to facilitate oxidation. To the mixture of a polymerizable oil with a drier, a suitable volatile solvent may be added for the purpose of facilitating Application filed May 12, 1925. Serial No. 29,798.

spreading the oil and insuring that the oil penetrates and Waterproofs \the joint between the top wad and the shell body. According to a preferred method of preparing the waterproofing composition, the polymerizable oil and the drier in suitable proportions are heated to 'ether. to a temperature which will vary with the particular oil andtheparticular drier used. The appropriate quantity of volatile solvent is added to the heated mixture which is allowed to cool. After cooling, a small quantity of the polymerizable oil may be added as it has been found that such an additionserves to retard the drying of the oil and to insure a more perfect waterproofing. One composition which has been found to give very satisfactory results comprises Chinese wood oil and a drier of manganese resinate and lead oxide, digested in carbon tetrachloride, this composition being prepared as follows: A mixture comprising about 37 parts of Chinese wood oil, one part' of manganese resinate and eight parts of lead oxide is brought to the temperature of about 220 C. and maintained at this temperature for a period of about ten minutes. Ninety-five parts of carbon tetrachloride are then added and the composition is allowed to cool. After cooling a small quantity of the Chinese wood oil is added. Other driers such as lead tungate, lead resinate, or cobalt tungate may be used, or the drier may be omitted altogether, likewise other volatile solvents, such as 'gas oline, turpentine and kerosene may be used. For example, excelthe exposure to heat, chemical agents, gasesor ,air at ordinary temperature. very satisfactory drying is effected by exposure to the air for periods varying from two to five hours.

We claim:

1. A loaded paper shot cartridge having the top wad and the crimp sealed and impregnated with a composition containing a polymerizable oil and a drier comprising manganese resinate and lead oxide in suitable proportions;

2. A loaded paper shotcartridge having the top. wad and the crimp sealed and impregnated'with a composition containing a polymerizable oil and ,a drier of manganese resinate and lead oxide digested in a suitable volatile solvent.

- 3. A loaded paper shot cartridge having the top wad and the crimp sealed and impregnated with a composition containing a polymrizable' oil and a drier containing manganese resinate and lead oxide in the proportions of one partof manganese resinate to eight'pa'rts of lead oxide.

4. A loaded paper shotcartridge having the top wad and the crimp sealed and impregnated with a composition containing Chinese wood oil, manganese resinate, and

lead oxide," and carbon tetrachloride in the following proportions 5. A loaded paper shot cartridge having the top wad and the crimp sealed and im pregnated with a composition containing substantially 37.5 parts of Chinese wood oil,

lpart of manganese res'inate' and 8 parts of i lead oxide heated to about 220 C. and di-' gested in 95 parts of carbon tetrachloride,

and having a small quantity of Chinese wood oil added thereto, subsequent to coolg STANLEY L. WILLIS.

WATSON H. WOODFORD. 

